Hydraulic press



Sept. 4,"'l923.

H. T. SHRIVER HYDRAULIC PRESS Filed June 11, 1920 INVENTOR. x /n/P/Py TSHIP/V515;

a 2 ATTORNEYS Patented Sept. 4, 1923.

UNITED STATES v 1,467,201 PATENT OFFICE.

HARRY 'r. SERIVEB, or LLEWELLYN PARK, NEW JERSEY.

HYDRAULIC rnnss.

Application filed June 11, 1920. Serial No; 388,171.

My present invention relates to hydraulic presses, and particularly tosuch presses which have a very long platen which is raised by aplurality of hydraulicpressureperated plungers.

One of the objects of my invention is to provide an arrangement by whichthe sticking or binding of the laten either on its guides or on thehydrau ic plungers will be prevented. I

lVith this and other objects in view, my invention consists ,of thearrangements and constructions hereinafter described and morespecifically pointed out in the appended claims. 1

The drawing shows a sideelevation of one form of hydraulic press towhich one form of my invention has been applied.

On a support 10 is mounted a plurality of hydraulic cylinders 11 in eachof which is mounted the usual plunger 12, each cylinder 11 having thenecessary piping and connections so that hydraulic pressure-maybeapplied below the plunger 12'to lift it, in the form shown all thecylinders being connected to the same source of pressure. Sup ported bythe plungers 12 is a platen 13 which, as shown, is very long and has inthe form illustrated twelve plungers spaced along it.

Above the platen v13 is a fixed head 14 toward which the platen 13 islifted to exert pressure on any material placed between the platen 13and the head 14. The reaction from such a pressure is taken up by rods15 held by nuts 16 and 17. It will be understood that the platen 13 andthe head 14 may be of any desired width and that there may be as manyrows of hydraulic cylinders across the press as may be desired, and thatthe rods 15 will be repeated on the opposite sides of the press. 1 Y

The construction so far described is old, and further detaileddescription thereof will be unnecessary.

It has been found that'in the operation of such a press it frequentlyoccurs that, because of the failure of the hydraulic plungers at one endto lift that end of the platen as. soon as the opposite end begins tolift, there is a cramping and binding of the platen. either on theguides 18 which are fastened to the'platen and slide on the rods 15,or," in some cases, the plungers themselves may stick and bind becauseof the tiltingof thelplaten- The lifting at one end before theothers'may arise from any one of a numberof'causes, such as theimperfect operation of the packing of the plungers or the-like. Whensuch sticking occurs it has been the practice heretofore to release thepressure to allow the platen to drop to its initial position and startit up again, this being repeateduntil through some combination ofcircumstances the two ends of the platen will rise together. i

'I have overcome this difiiculty by providing a means by which the twoends of. the platen are compelled to rise together, irrespective of anyjdifferences which may exist in'th'e operation of the plungers at eitherend of the platen. As one form of apparatus for this purpose I haveshown a device indicated in the drawing, in which cables are connectedto opposite ends of the platen in such a manner that the lifting of oneend will necessarily cause the other end to'lift also.

The cable 20 is fastened at 21 to one endv of the platen 13 andpassesover a pulley 22 supported on a housing connected to thehea'd 14:.From this pulley 22 the cable 20 passes over a pulley 23 and from thenceover a pulley 24, connected to the support for the hydraulic cylinders.

From" the pulley 24' the cable passes to a fastening member 25 whichattaches it tothe opposite end of the platen 13. Similarly,

a cable 26 is attached at 27 to one end of I the platen and passes overpulleys 28 and 29 'on thehea'd' 14 and over a pulley-3O on exerted onthecorresponding cable to cause a liftingpressureion the opposite end ofthe platen, so that there can be no tilting of the platen to cause abinding on the guides or plungers. my arrangement answers its purpose ifit It will also be understood that exerts only a comparatively smalllifting pressure, because the lifting force on each of the hydrauliccylinders is substantially the same, and the only dilferences which arenecessary to be taken up are such as may arise through defects inplunger packings and the like, which defects are minimized, if notentirely overcome, provided the hydraulic plunger is kept perfectlyvertical, and is not given a side pressure such as would arise if oneend of the long platen should rise before the other.

The possibility of the platen tipping may also arise through thecarrying of greater weights on one end of theplaten than on the other,such, for instance, as mechanism for drawing materials along the surfaceof the platen 13, which mechanism may all be located at one end of theplaten. Sucha weight would tend, of course, to unbalance the platen andmy equalizing device will compensate for such unbalancing.

It will also be understood that by cables, I mean any flexible member,such as a chain, steel cable or the like, which will not stretchmaterially under the tension to which it may be subjected. v

Obviously, the equalizing device will be effective if it connectsportions of the platen on either side of the center of'balance. For-thebest effects, however, it is desirable that the connections be placedwell toward the respective ends of the platen, so that a slight tiltingof the platen 'will I bev imniediately eifectiveto raise the oppositeend. In the appended claims,'when I refer to the ends of the platen, itwill be understood that I- mean any of the portions on one side of thecenter, and not necessarily the extremities of the platen. I

I claim:

1. In a hydraulic press, a long platen, a plurality of fluid-actuatedplung'ers spaced apart and beneath said platen and adapted to lift it,and an equalizing device independent of the plunger pressure supplycontrolling devices connected to saidplaten and constructed and arrangedto' cause the top of the platen to remain parallel 'to its initialposition as it is raisedby said plungers, irrespective ofdiifi'erencesin the operation of said plungers.

2. In a hydraulic press. along platen, a plurality of fluid-actuated plungers spaced apart and beneath said platen and-adapted to lift it, andan equalizing device independent of the plunger pressure supplycontrolling devices connected to opposite ends of said platen andconstructed and arranged to cause the top of the platen to remainparallel to its initial'position as it"is raised by said plungers,irrespective. of differences in the operation of said plungers.

3. In a hydraulic press,'a long platen, a plurality of fluid-actuatedplungers spaced apart and beneath said platen and adapted to lift it,and an equalizing device, connecting opposite portions of said platen oneither side of the center of balance and constructed and arrangedtocause the top of the platen to remain parallel to its initial positionas it is raised by said plungers.

4. In a hydraulic press, a long platen, a plurality of fluidactuatedplungers spaced apart and beneath said platen and adapted tolift it,guides for said platen, and an equalizing device, comprising a memberconnecting the opposite ends of said platen and constructed and arrangedto equalize the motion given to said platen. by the several plungers,whereby binding of the guides will be prevented, irrespective ofdifferences in the operation of said plungers.

5. In a hydraulic press, a long platen, a plurality of fluid-actuatedplungers spaced apart and beneath said platen and adapted to lift it,guides for said platen, and an equalizing device, comprising a memberconnecting opposite portions of said platen on either side of the centerof balance, and constructed and arranged to cause the top of the platento remain parallel to its initial position as it is raised by theplungers.

6. In a hydraulic press, a long platen, a plurality of fluid-actuatedplungers spaced apart and beneath said platen and adapted to lift it, asupport for said plungers, head towards which the platen is lifted andan equalizing device, comprising a pair of cables connecting oppositeends of said platen, and pulleys for said cables, constructed andarranged to cause the opposite ends of said platen to rise together,irrespective of differences in the operation of said plungers.

7. In a hydraulic press, a long platen, a plurality of fiuid-actuatedplungers spaced apart and beneath said platen and adapted to lift it, asupport for said plungers, ahead towards which the platen is lifted andan equalizing device, comprising a pair of cables on either side of saidplaten, each having its opposite ends connected to said platen, andpulleys for said cables, con structed and arranged to cause the oppositeends of said platen to rise together, irrespective of differences in theoperation of said plungers.

8. In a hydraulic press, a long platen, a plurality of fluid a'ctuatedplungers spaced apart and beneath said platen and adapted tolift it, a:supportfor said plungers; a. headtowards which the platen isl-ifted andan equalizing device, comprising a pair of cables on either side of saidplaten, each hav ing; its opposite ends connected to said platen, andpulleys over which said cables pass, each cable passing over a pulleyat-each end of said head and a pulley on said support at one end ofsaid'p'laten.

9. In a hydraulic press, a long platen, a plurality of fluid-actuatedplungers spaced apart and adapted to actuate said platen, and anequalizing device independent of the plunger pressure supplycont-rolling devices connected to said platen, and constructed andarranged to cause the platen to remain parallel to its initial positionas it is raised by said plungers, irrespective of diiferences in theoperation of said plungers.

10. In a hydraulic press, a, long platen, a plurality of fluid-actuatedplungers spaced apart and adapted to actuate said platen, and anequalizing device independent of the plunger pressure supply controllingdevices connected to opposite ends of said platen and constructed andarranged to cause the platen to remain parallel to its initial positionas it is raised by said plungers, irrespective of differences in theoperation of said plungers.

11. In a hydraulic press, a long platen, a plurality of fluid-actuatedplungers spaced apart, and adapted to actuate said platen, and anequalizing device, connecting opposite portions of said platen on eitherside of the center of balance and constructed and arranged to cause theplaten to remain parallel to its initial position as it is raisedv bysaid plungers.

12. In a hydraulic press, a long platen, a plurality of fluid-actuatedplungers spaced apart and adapted to actuate said platen guides for saidplaten, and an equalizing device, comprising a member connecting theopposite ends of said platen and constructed and arranged to equalizethe motion given to said platen by the several plungers, whereby bindingof the guides Will be prevented, irrespective of difi'erences in theoperation of said plungers.

13. In a hydraulic press, a long platen, a plurality of fluid-actuatedplungers spaced apart and adapted to actuate said platen guides for saidplaten, and an equalizing device, comprising a member connectingopposite portions of said platen on either side of the center ofbalance, and constructed and arranged to cause the platen to remainparallel to its initial position as it is raised by the plun ers.

HKRRY T. SHRIVER.

